45

Conduct of Examinations at Levels 1 and 2

Non-Destructive Testing: Sample Questions for
Non-Destructive Testing:
Sample Questions for
Conduct of Examinations
at Levels 1 and 2

Training Course Series

ISSN 1 0 1 8 – 5 5 1 8 Vienna, 2010 Training Course Series

45
13.24 mm
 3 RADIOGRAPHIC TESTING (RT)

3.1 Radiographic Testing Level 1 (RT-1)

3.1.1 Radiographic Testing Level 1 (RT-1) General Examination

1. Which of the following types of intensifying screens are not used in industrial
radiography?

(a) Lead

(b) Fluorescent

(c) Silver halide

(d) All of the above

2. Betatrons are used to produce X rays in what range?

(a) Several MeV

(b) 50-500 keV

(c) 500-1000 keV

(d) 0-50 keV

3. Which of the following is an isotope not artificially produced for industrial use:

(a) Ir-192

(b) Ra-226

(c) Co-60

(d) All of the above

4. One half value layer of lead for Iridium-192 is approximately:

(a) 12 mm

(b) 4 mm

(c) 2 mm

(d) 25 mm

106
5. One half value layer of lead for Cobalt-60 is approximately:

(a) 12 mm

(b) 6 mm

(c) 2 mm

(d) 25 mm

6. The film processing step in which the undeveloped silver bromide is removed from
the film emulsion is called:

(a) Development

(b) Stop bath

(c) Fixing

(d) Rinsing

7. A radiation producing device which emits radiation of one or a few discreet

wavelengths is:

(a) An X ray machine

(b) A linear accelerator

(c) A gamma ray source

(d) A betatron

8. The intensifying action of lead screens is caused by:

(a) Secondary X ray emission

(b) Secondary gamma ray emissions

(c) Fluorescence of lead screens

(d) Electron emission

9. Most of the energy applied to an X ray tube is converted into:

(a) X rays

(b) Light

(c) Heat

(d) Ultraviolet radiation

107
 10. Radiography of tubular sections using a double wall, double viewing technique is
mainly applicable to sections:

(a) Over 38 mm in diameter

(b) 88 mm in diameter or less

(c) 125 mm in diameter and less

(d) Under 25 mm in diameter

11. Which of the following is the most common method of packaging film?

(a) Individual sheets for use in cassettes

(b) Rolls

(c) Pre-packaged (‘day-pack’)

(d) All of the above

12. Which of the following types of radiation is particulate?

(a) X

(b) Gamma

(c) Alpha

(d) None of the above

13. Most scattered radiation which adversely affects the radiographic image quality
originates:

(a) From floors and walls adjacent to the test piece

(b) From other nearby objects

(c) From the test piece itself

(d) From the lead intensifying screens

14. An effect of scattered radiation is to:

(a) Decrease required exposure time

(b) Diminish contrast, detail and clarity of radiographic image

(c) Decrease film density

(d) All of the above

108
15. What is the most important factor in determining the archival quality of radiographic
film?

(a) Film density

(b) Image quality

(c) Degree of removal of fixer residues during washing

(d) Degree of removal of developer residues during washing

16. Radiographic enlargement to distinguish small defects is possible:

(a) Only with a very small source or focal spot size radiation source

(b) Routinely

(c) With most sources

(d) Never

17. A detrimental effect of fluorescent screens might be:

(a) High definition

(b) Screen mottle

(c) Non-linear attenuation

(d) Displaced core effect

18. The penetrating power of an X ray machine is indicated by:

(a) Milliamperage

(b) Tube voltage

(c) Filament current

(d) Anode current

19. Reticulation may be the result of:

(a) Inadequate agitation of the film during development

(b) Inadequate water rinse during processing

(c) Using exhausted stop bath solution

(d) Developing solutions not maintained at the same temperatures.

109
 20. The main advantage of having small focal spot on an X ray tube is:

(a) Heat is conducted away more efficiently than with a large focal spot

(b) A smaller focal spot is unlikely to be damaged from the required tube currents

(c) Longer tube life

(d) A smaller focal spot allows sharper radiographic images than does a larger
focal spot

21. Cobalt-60 is produced by:

(a) Fission of Uranium-235

(b) Neutron capture by Cobalt-59

(c) Radioactive decay

(d) None of the above

22. For a particular isotope, gamma radiation intensity is determined by:

(a) Type of isotope used

(b) Energy level of gamma rays in source

(c) Source strength in curies

(d) None of the above

23. Which of the following statements should be true to achieve the highest level of
radiographic sharpness (definition)?

(a) The focal spot should be as small as practicable

(b) The focal spot to test piece distance should be as large as practicable

(c) The film to test piece distance should be as small as practicable

(d) All of the above

24. Which of the following correctly expresses the inverse square law if I1=dose rate
nearest source, I2=dose rate furthest from the source, D1=distance nearest to source
and D2=distance furthest from the source:

(a) I1/I2 = D12/D22

(b) I12/I22 = D1/D2

(c) I1/I2 = D22/D12

(d) I12/I22 = D2/D1

110
25. Thicker materials would normally be inspected using:

(a) Lower kV X rays

(b) Higher mA X rays

(c) Higher kV X rays

(d) Lower mA X rays

26. Another name for a penetrameter is:

(a) Radiographic shim

(b) Image quality indicator

(c) Density standard

(d) Acceptance standard

27. The silver nitrate spot test can be used to:

(a) Check the film for film quality

(b) Check for under developed films

(c) Check for film artifacts

(d) All the above answers are correct

28. The difference in densities seen on a radiograph due to section changes in an item is:

(a) Film contrast

(b) Radiographic contrast

(c) Subject contrast

(d) Radiographic sensitivity

29. Which type of film would exhibit the coarsest grain?

(a) Slow

(b) Medium

(c) Fast

(d) No difference in the grain sizes

111
 30. An advantage of a gamma ray source is:

(a) Radiation may be turned on or off at will

(b) Outside power is normally not required

(c) Less shielding is required than for X ray

(d) All of the above

31. Higher X ray tube voltages result in:

(a) Shorter wavelengths X rays

(b) Less penetrating X rays

(c) Fewer X rays in the primary beam

(d) All of the above

32. A casting flaw which is formed when two masses of molten metal flowing from
different directions flow together, but fail to fuse, is called:

(a) A hot tear

(b) Shrinkage

(c) A cold crack

(d) A cold shut

33. X rays are produced by:

(a) Radioactive isotopes

(b) The rapid deceleration of electrons

(c) Ultraviolet radiation of unstable atoms

(d) All of the above

34. Which of the following is a function of lead screens?

(a) To reduce geometric unsharpness

(b) To increase scatter

(c) To reduce exposure time

(d) All of the above

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35. A silver nitrate spot test might be used to:

(a) Check for archival film quality

(b) Check for out of date film

(c) Check for single versus double emulsion film

(d) Any of the above

36. A linear accelerator is used to produce X rays having energy in the range of:

(a) Several MeV

(b) 50-500 keV

(c) 500-1000 keV

(d) 0-50 keV

37. How is the wavelength of scattered radiation compared to the primary beam?

(a) Longer than the wavelength of the primary beam

(b) Shorter than the wavelength of the primary beam

(c) Same as the wavelength of the primary beam

(d) Not related

38. Which of the following viewing conditions is most desirable for interpreting
radiographic film?

(a) Brightness of surroundings approximately the same as the area of interest on

the radiograph

(b) Totally dark viewing room

(c) Well lit viewing room

(d) None of the above

39. Pinhole radiography would be used to:

(a) Make high quality radiographs for critical inspection

(b) Determine focal spot size

(c) Construct exposure charts

(d) None of the above

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 40. A straight, dark line in the centre of the film of a weld cap would probably be:

(a) Porosity

(b) Undercut

(c) Tungsten inclusions

(d) A linear crack

41. Which one of the following steps is necessary to dissolve the undarkened silver salt
crystals in the film emulsion:

(a) Developing

(b) Fixing

(c) Washing

(d) None of the above

42. Approximately what energy X ray machine would be required to have penetrating
power equivalent to a Cobalt-60 source:

(a) 600 keV

(b) 1.2 MeV

(c) 2 MeV

(d) None of the above

43. The normal range of steel that is radiographed using Ir-192 is:

(a) 5 mm–20 mm

(b) 25 mm – 75 mm

(c) 0.5 mm – 5 mm

(d) 75 mm – 150 mm

44. The focal spot size of an X ray machine must be known in order to determine:

(a) The geometric unsharpness

(b) Kilovoltage peak output

(c) Required mA setting

(d) Exposure time

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45. X ray intensity is a function of :

(a) Cathode current

(b) Step down ratio of the filament transformer

(c) The distance from the test piece

(d) Size of the anode (target)

46. What is the minimum age in years at which a person may perform radiography :

(a) 15

(b) 18

(c) 21

(d) 30

47. A densitometer is an instrument that measures:

(a) Radiographic contrast

(b) Radiographic sensitivity

(c) Radiographic density

(d) Radiographic resolution

48. Which of the following is the correct formula to use for calculating geometric
unsharpness if F=source size, T=specimen thickness, D=source to object distance and
Ug=geometric unsharpness:

(a) Ug = FD/T

(b) Ug = DT/F

(c) Ug = FT/D

(d) Ug = FTD

49. A wetting agent is used in film processing to:

(a) More closely control development

(b) Prevent formation of water marks during the drying stage

(c) Reduce formation of air bubbles in the developer solution

(d) Reduce formation of air bubbles in the fixer

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 50. Film intensifying screens are normally used to:

(a) Decrease exposure time

(b) Increase grain size

(c) Shield film from stray light

(d) All of the above

51. A radiation producing device which emits a broad spectrum of wavelengths is:

(a) A gamma ray source

(b) An X ray machine

(c) A Geiger-Müeller tube

(d) A curie tube

52. Which of the following represent types of radiation stemming from radioactive decay :

(a) Alpha, beta, gamma

(b) Alpha, gamma, delta

(c) X, rho, sigma

(d) Sigma, gamma, beta

53. Explain the difference between X and gamma rays:

(a) They are both types of electromagnetic radiation

(b) X rays are naturally occurring; gamma rays are man made

(c) X rays are produced electrically; gamma rays are emitted by disintegrating
atomic nuclei

(d) There is no difference

54. Most industrial X ray machines contain targets made of:

(a) Beryllium

(b) Magnesium

(c) Lead

(d) Tungsten

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55. The effects of scattered radiation may be lessened by:

(a) Using a lead mask around the test piece

(b) Using a lead or copper filter between the X ray tube and the test piece

(c) Using lead screens

(d) All of the above

56. A reaction which occurs when a radiation beam of 500 keV is partially absorbed by a
test piece would probably be:

(a) The Compton effect

(b) The photoelectric effect

(c) Pair production

(d) Any of the above

57. The term used to describe the reaction of human cells, other than reproductive cells, to
ionizing radiation is:

(a) Genetic effects

(b) Somatic effects

(c) Corpuscular effects

(d) Hematological effects

58. A low density image of the letter ‘B’ on a radiographic film would probably be caused
by:

(a) Under exposure

(b) Excessive exposure

(c) Excessive backscatter

(d) Insufficient backscatter

59. A term which refers to the sharpness of the radiographic image is:

(a) Sensitivity

(b) Halo effect

(c) Shadow effect

(d) Definition

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 60. A dark, irregular indication which is located adjacent to the toe of the weld would
probably be:

(a) Undercut

(b) Incomplete penetration

(c) Porosity

(d) Tungsten inclusions

61. A term which refers to the smallest detail visible in a radiograph is called:

(a) Radiographic sensitivity

(b) Radiographic contrast

(c) Subject contrast

(d) Film contrast

62. Which type of gamma ray source would be used to radiograph a weld in 150 mm thick
steel plate?

(a) Ir-192

(b) Co-60

(c) Tm-170

(d) Cs-137

63. The radiation quality of a gamma ray source is determined by:

(a) The size of the source

(b) The type of isotope to be used

(c) Can be varied by the operator

(d) Ci strength of the source

64. Generally, X ray output is changed by changing the:

(a) Atomic number of the anode

(b) Tube current of the unit

(c) Supply voltage to the unit

(d) Atomic weight of the cathode

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65. Deep scratches on lead intensifying screens will cause?

(a) Selective image enhancement

(b) Irregular light lines on the film

(c) Dark lines on the film

(d) Unacceptable blockage of the primary radiation beam

66. Which of the following is classified as electromagnetic radiation?

(a) Visible light

(b) X rays

(c) Infrared radiation

(d) All of the above

67. The main disadvantage of having a small focal spot on an X ray tube is:

(a) Heat is conducted away too fast

(b) Sharper radiographic images may be achieved with a larger focal spot

(c) A smaller focal spot is limited to lower tube currents because of the potential
damage from overheating

(d) None of the above

68. Exposure of whole body to moderate radiation doses of 500 – 2000 mSv (50 to
200 rem) would probably cause which of the following effects?

(a) Blood cell changes

(b) Swelling

(c) Possible nausea

(d) All of the above

69. A reaction which occurs when a radiation beam of 90 keV is totally absorbed by a test
piece would probably be:

(a) The Compton effect

(b) The photoelectric effect

(c) Pair production

(d) Any of the above

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 70. The term used to describe the reaction of human reproductive cells, to ionizing
radiation is:

(a) Genetic effects

(b) Somatic effects

(c) Corpuscular effects

(d) Hematological effects

71. Explain the difference between X and gamma rays:

(a) They are both types of electromagnetic radiation

(b) X rays are naturally occurring; gamma rays are man made

(c) X rays are produced electrically; gamma rays are emitted by disintegrating
atomic nuclei

(d) There is no difference

72. Which of the following is classified as electromagnetic radiation?

(a) Visible light

(b) X rays

(c) Infrared radiation

(d) All of the above

73. The intensifying action of lead screens is caused by:

(a) Secondary X ray emission

(b) Secondary gamma ray emissions

(c) Fluorescence of lead screens

(d) Electron emission

74. How is the wavelength of scattered radiation related to the primary beam?

(a) Longer

(b) Shorter

(c) Same

(d) Not related

120
75. X rays are produced by:

(a) Radioactive isotopes

(b) The rapid deceleration of electrons

(c) Ultraviolet radiation of unstable atoms

(d) All of the above

76. Most of the energy applied to an X ray tube is converted into:

(a) X rays

(b) Light

(c) Heat

(d) Ultraviolet radiation

77. Higher X ray tube voltages result in:

(a) Shorter wavelengths X rays

(b) More penetrating X rays

(c) Higher intensity X ray beam

(d) All of the above

78. Betatrons are used to produce X rays having energy in the range of:

(a) Several MeV

(b) 50-500 keV

(c) 500-1000 keV

(d) 0-50 keV

79. A linear accelerator is used to produce X rays in what range?

(a) Several MeV

(b) 50-500 keV

(c) 500-1000 keV

(d) 0-50 keV

121
80. For a particular isotope, gamma radiation intensity is determined by:

(a) Type isotope used

(b) Energy level of gamma rays in source

(c) Source strength in curies

(d) None of the above

81. A term used to describe the range of radiation intensities falling on the film during
exposure is:

(a) Film contrast

(b) Radiographic contrast

(c) Subject contrast

(d) Radiographic sensitivity

82. An expression which is used to describe the slope of a film characteristic curve is:

(b) Film latitude

(c) Film contrast

(d) Film sensitivity

(e) Film gradient

83. Which of the following factors affect film graininess?

(a) Wavelengths of radiation

(b) Film processing conditions

(c) Film speed

(d) All of the above

84. The amount of radioactivity which corresponds to 3.7 × 1010 disintegrations per second
is called:

(a) 0.01 gray (1 rad)

(b) 1 Farad

(c) 37 GBq (1 curie)

(d) 10 mSv (1 roentgen)

122
85. The result of filtering the X rays is to produce:

(a) More geometric unsharpness

(b) Less geometric unsharpness

(c) Softer radiation

(d) Harder radiation

86. Which of the following actions is performed by lead screens?

(a) Absorbs a portion of the primary radiation beam

(b) Preferentially absorbs soft X rays

(c) Emits electrons under gamma and X ray fields

(d) All of the above

87. The total radiation dose received equals:

(a) The radiation intensity

(b) The source size in curies

(c) Radiation intensity times time of exposure

(d) Radiation intensity divided by the square of the distance from the source

88. Which of the following is the most common type of X ray tube?

(a) Bipolar

(b) Unipolar

(c) Long anode

(d) None of the above

89. A reaction which occurs when a radiation beam of 15 MeV is partially absorbed by a
test piece would probably be:

(a) The Compton effect

(b) The photoelectric effect

(c) Pair production

(d) Any of the above

123
90. A reaction which occurs when a radiation beam of 50 keV is partially absorbed by a test
piece would probably be:

(a) The Compton effect

(b) The photoelectric effect

(c) Pair production

(d) Any of the above

91. A lethal dose of complete body radiation is normally considered to be:

(a) 1-2 Sv (100-200 rem)

(b) 250-500 mSv (25-50 rem)

(c) 6-8 Sv (600-800 rem)

(d) 500 mSv (50000 mrem)

3.1.2 Radiographic Testing Level 1 (RT-1) Specific Examination

1. Almost all gamma radiography today is done with artificially activated:

(a) Particles

(b) Isotopes

(c) Radium

(d) X ray machines

2. A Curie (37 gigabecquerel)of radioactive material will disintegrate at the rate of:

(a) 37 million (3.7 × 107) disintegrations per second

(b) 37 billion (3.7 × 1010) disintegrations per second

(c) 37 trillion (3.7 × 1013) disintegrations per second

(d) None of the above

3. The specific activity of radioactive isotopes is measured in:

(a) MeV (million electron volts)

(b) R/h (roentgens per hour) or gray per hour

(c) Ci/g (curies per gram) or Becquerel per gram

(d) Counts per minute (c/min)

124
4. What is the primary difference between X rays and gamma rays of the same energy?

(a) Wavelength

(b) Frequency

(c) Velocity

(d) Origin

5. Screens should be:

(a) Separated from the film by a sheet of clean white paper

(b) Separated from the film by at least 3.125 mm

(c) In direct contact with the film

(d) Separated from the film by its cardboard backing

6. Lead foil in direct contact with the film in a cassette absorbs:

(a) All radiation to protect the film from exposure

(b) Light rays that might otherwise expose the film

(c) Long wave length radiation more than short wavelength

(d) Short wavelength radiation more than long wavelength

7. Lead screens improve mainly the _______________________ of the final radiograph:

(a) Density

(b) Contrast

(c) Exposure

(d) Definition

8. Lead foil is placed behind the films to:

(a) Absorb as much side scatter as possible

(b) Reduce non image forming back-scatter

(c) Reduce the quality of image-forming primary rays

(d) Limit the amount of light striking the film.

125
 9. A filter will reduce the amount of _______________ in the primary radiation beam:

(a) Scatter

(b) Electrons

(c) High energy radiation

(d) Low energy radiation

10. A filter is placed:

(a) Between the source and the specimen

(b) Between the specimen and the film

(c) Around the specimen

(d) Behind the film

11. The tube current in milliamps multiplied by the time in seconds or minutes equals:

(a) Density

(b) Intensity

(c) Exposure

(d) Kilovoltage

12. If we were to maintain the same exposure but decrease the source to film distance, we
must ________________ the time of exposure:

(a) Increase

(b) Decrease

13. Lead screens act as intensifiers at voltage above:

(a) 1000 kV

(b) 150 kV

(c) 325 kV

(d) 2000 kV`

126
14. Use of a slower speed film improves the definition of the radiograph because the
slower film:

(a) Requires more exposure

(b) Is more sensitive to X rays

(c) Requires less voltage

(d) Has finer grains

15. The penetrameter is a tool used to check the ________________ of a radiograph:

(a) Contrast

(b) Definition

(c) Sensitivity

(d) Emulsion

16. When using a radioactive isotope in making a radiograph, we can express the equation
for exposure as Ci × T. In this equation , Ci stands for:

(a) Current through tube

(b) Intensity in curies or becquerels

(c) Degree of contrast

(d) Coarseness of the film

17. In the radiographic analysis procedure that is used to prepare an exposure chart, the
first step is to:

(a) Make a series of radiographs of a step wedge

(b) Radiograph several objects of known thickness

(c) Convert the densities read from the radiographs to a standard density

(d) Plot the exposures on a graph

18. Which exposure factors are recorded in the process of making a step wedge analysis?

(a) Voltage and exposure

(b) Source-to-film distance and film

(c) Film density and materials

(d) All of the above

127
 19. After the step wedge radiographs have been made, the ____________ of the image of
each step is recorded on chart:

(a) Sharpness

(b) Contrast

(c) Density

(d) Length

20. The process of loading more than one film into a cassette is known as the
___________ technique:

(a) Single film technique

(b) Multiple film technique

21. Which of the following isotopes are commonly used for radiographic purposes?

(a) Iridium-192

(b) Osmium-188

(c) Cobalt-87

(d) Rubidium

22. The process of being radioactive is called (Choose one):

(a) Heating

(b) Decaying

(c) Bremsstrahlung

(d) Rectification

23. Which of the following types of radiation is commonly used in radiographic testing?
(Choose one):

(a) Alpha particles

(b) Neutrons

(c) gamma rays

(d) Beta rays

128
24. The amount of X radiation or gamma radiation is often spoken of as the
____________ of the radiation:

(a) Wavelength

(b) Energy

(c) Intensity

(d) Frequency

25. The speed at which X and gamma rays travel is: (choose one)

(a) The speed of light

(b) The speed of sound

(c) It varies with the wavelength

(d) Depends on the source

26. A beam of radiation consisting of a single wavelength is known as: (choose one)

(a) Microscopic radiation

(b) Monochromatic radiation

(c) Heterogeneous radiation

(d) Fluoroscopic radiation

27. What governs the penetrating ability of an X ray beam?

(a) Kilovoltage

(b) Time

(c) Activity

(d) Milliamperage

28. The shorter the wavelength of X or gamma rays:

(a) The higher their energy

(b) The faster they travel

(c) The greater their intensity

(d) The closer they are to becoming radio waves

129
 29. ‘Photoelectric effect’ refers to:

(a) An electric camera

(b) Complete absorption of a photon

(c) The visible electromagnetic spectrum

(d) Scatter of neutrons

30. When a tissue cell in human body is damaged by radiation:

(a) The cell may lose its ability to reproduce

(b) The cell may die

(c) Damage is caused by knocking an electron out of the orbit of its parent atom.

(d) All of the above

31. Lead intensifying screens are used to:

(a) Decrease exposure time

(b) Increase grain size

(c) Shield film from stray light

(d) All of the above

32. An effect of scattered radiation is to:

(a) Decrease required exposure time

(b) Diminish contrast, detail and clarity of radiographic image

(c) Decrease film density

(d) All of the above

33. The effects of scattered radiation may be lessened by:

(a) Using a lead mask around the test piece

(b) Using a lead or copper filter between the X ray tube and the test piece

(c) Using lead screens

(d) All of the above

130
34. Radiographic film speed can be increased by using:

(a) A higher mA setting

(b) A lower mA setting

(c) A double emulsion versus a single emulsion film

(d) Lead screens versus fluorescent screens

35. An advantage of a gamma ray source is:

(a) Radiation may be turned on or off at will

(b) Outside power is normally not required

(c) Less shielding is required than for X ray

(d) All of the above

36. A radiation producing device which emits radiation of one or a few discreet
wavelengths is:

(a) An X ray machine

(b) A linear accelerator

(c) A gamma ray source

(d) A betatron

37. A radiation producing device which emits a broad spectrum of wavelengths is:

(a) A gamma ray source

(b) An X ray machine

(c) A Geiger Mueller tube

(d) A curie tube

38. The primary effect of an increase in the milliamperage at which a X ray tube is being
operated would be to:

(a) Increase the radiation intensity

(b) Increase penetrating power

(c) Increase primary beam wavelengths

(d) All of the above

131
39. The primary effect of an increase in the kilovoltage at which a X ray tube is being
operated would be to:

(a) Increase the radiation intensity

(b) Increase penetrating power

(c) Increase penetrating power and radiation intensity

(d) Increase primary beam wavelength

40. Which of the following types of intensifying screens are used in industrial radiography?

(a) Lead

(b) Fluorescent

(c) Lead oxide

(d) All of the above

41. Which of the following expressions correctly describe the relation between
milliamperage (M) and focus-to-film distance (D)?

(a) M1/M2 = (D12)/(D22)

(b) M2/M1 = (D12)/(D22)

(c) M1/M2 = D1/D2

(d) M1/M2 = D2/D1

42. Which of the following expressions correctly describes the relation between exposure
time (T) and focus-film distance (D)?

(a) T1/T2 = (D12)/(D22)

(b) T2/T1 = (D12)/(D22)

(c) T1/T2 = D1/D2

(d) T1/M2 = D2/D1

43. Which of the following expressions correctly describes the relation between
milliamperage (M) and exposure time (T)?

(a) M1/M2 = T1/T2

(b) M2/M1 = T12/T22

(c) M1/M2 = T22/T12

(d) M1/M2 = T2/ T1

132
44. A change in which of the following parameters would necessitate the construction of a
new X ray exposure chart?

(a) X ray machine used

(b) Film type

(c) Focal spot to film distance

(d) Any of the above

45. The ASTM penetrameter for a 25 mm thick test piece contains holes of what sizes?

(a) T, 2T, 3T

(b) 2T, 3T, 4T

(c) T, 2T, 4T

(d) T, 3T, 4T

46. The minimum size hole in an ASTM penetrameter is:

(a) 0.127 mm (0.005 inches)

(b) 0.254 mm (0.010 inches)

(c) 0.508 mm (0.020 inches)

(d) 0.762 mm (0.030 inches)

47. A radiographic sensitivity level of 2-2T means that:

(a) The #2 hole in a #2 penetrameter must be visible on the film

(b) The 2T hole in a penetrameter which is 2% of the test piece thickness must be
visible on the film

(c) The 2T hole in a #2 penetrameter must be visible on the film

(d) Two penetrameters which are each 2% of the test piece thickness must be used

48. What is the most desirable temperature for manual developer solutions?

(a) 15.5oC (60oF)

(b) 20oC (68oF)

(c) 22.2oC (72oF)

(d) 26.6oC (80oF)

133
49. What is the longest period of time which should elapse between complete changes of
developer solution?

(a) 1 week

(b) 2 weeks

(c) 1 month

(d) 3 months

50. A possible result of failing to use a stop bath during manual development is:

(a) Streaking of the film

(b) Underdevelopment of the film

(c) Contamination of the developer solution

(d) Developer solution drag-out

51. Mottled film may result from:

(a) Inadequate agitation of the film during development

(b) Inadequate water rinse during processing

(c) Using exhausted stop bath solution

(d) Any of the above

52. Radiography of tubular sections using a double wall, double viewing technique is
mainly applicable to sections:

(a) Over 38 mm in diameter

(b) 88 mm in diameter or less

(c) 125 mm in diameter and less

(d) Under 25 mm in diameter

53. A thin, white line within the film image of a weld crown might be:

(a) A hair between the lead screen and the film

(b) Incomplete penetration

(c) A crack

(d) Undercut

134
3.1.3 Radiographic Testing Level 1 (RT-1) Answers to questions

Radiographic Testing Level 1 Answers to Questions

General Examination Specific Examination
1 c 35 a 69 b 1 b 35 b
2 a 36 a 70 a 2 b 36 c
3 b 37 a 71 c 3 c 37 b
4 c 38 a 72 d 4 d 38 a
5 a 39 b 73 d 5 c 39 b
6 a 40 d 74 a 6 c 40 a
7 c 41 b 75 b 7 b 41 a
8 d 42 b 76 c 8 b 42 b
9 c 43 b 77 d 9 d 43 d
10 b 44 a 78 a 10 a 44 a
11 d 45 a 79 a 11 c 45 c
12 c 46 b 80 c 12 b 46 b
13 a 47 c 81 b 13 b 47 b
14 b 48 c 82 d 14 d 48 b
15 c 49 b 83 d 15 c 49 d
16 a 50 a 84 c 16 b 50 a
17 b 51 b 85 d 17 a 51 d
18 b 52 a 86 d 18 d 52 c
19 d 53 c 87 c 19 c 53 a
20 d 54 d 88 a 20 b
21 b 55 d 89 c 21 a
22 c 56 a 90 b 22 b
23 d 57 b 91 c 23 c
24 c 58 c 24 c
25 c 59 d 25 a
26 b 60 a 26 b
27 a 61 a 27 a
28 c 62 b 28 a
29 c 63 29 b
30 b 64 b 30 d
31 a 65 b 31 a
32 d 66 d 32 b
33 b 67 c 33 d
34 c 68 d 34 d

135
3.2 Radiographic Testing Level 2 (RT-2)

3.2.1 Radiographic Testing Level 2 (RT-2) General Examination

1. Increasing the kV setting on an X ray machine increases the:

(a) Penetrating power

(b) Short wavelength components of the X ray beam

(c) Radiation intensity

(d) All of the above

2. During the manufacturing of a casting, the purpose of a riser is:

(a) To introduce molten metal into the mould

(b) To provide additional molten metal to allow for shrinkage during solidification

(c) To allow excess heat to escape during solidification

(d) To provide a vent for excess steam to escape

3. An effective method of recognising a film artifact is:

(a) Viewing a film in daylight

(b) Viewing film in reflected light from a viewer

(c) Comparing both film shot with a double film technique

(d) All of the above

4. The main reason for using a casting is that:

(a) Castings are stronger than other metal product forms

(b) Castings are normally of higher quality than other metal product forms

(c) Complex shapes of minimum weight are easily manufactured

(d) None of the above

5. A change in which of the following parameters would require a new X ray exposure
chart?

(a) kV

(b) Required film density

(c) Test piece thickness

(d) All of the above

136
6. Static marks on radiographic film are caused by:

(a) An improperly grounded X ray tube

(b) Scratches on the lead screens

(c) Poor film handling technique

(d) Old film

7. Of the following radiographic sources, which emits the most penetrating radiation?

(a) Co-60

(b) Ra-226

(c) Cs-137

(d) Ir-192

8. Which of the following techniques would probably reduce the amount of back
scattered radiation reaching the film during a radiographic exposure?

(a) Using a finer grained film

(b) Backing the cassette with a sheet of lead

(c) Removing lead screens

(d) All of the above

9. Radiographic contrast is dependant on:

(a) Density

(b) Processing

(c) Radiation energy

(d) All of the above

10. A plot of film density versus log of relative exposure is called:

(a) An H&D curve

(b) A sensitometric curve

(c) A characteristic curve

(d) All of the above

137
 11. The most common material used for targets in X ray tubes is:

(a) Tungsten

(b) Copper

(c) Silver

(d) Beryllium

12. A dark crescent shaped spot, clearly in the base metal adjacent to a weld would
probably be:

(a) Burn through

(b) Film crimp mark

(c) A crack

(d) A water spot on the film

13. Which of the following are potential sources of scattered radiation?

(a) Test piece

(b) Cassette

(c) Floor

(d) All of the above

14. If the required exposure time for a 2220 GBq (60 curie) Ir-192 source is 2 minutes,
what exposure time would be required at 1110 GBq (30 curie) source:

(a) 2/3 minutes

(b) 60 minutes

(c) 2 minutes

(d) 4 minutes

15. An advantage of a larger grain film is:

(a) It has higher speed

(b) It has better definition

(c) It has lower speed

(d) None of the above

138
16. How does radiation intensity change with increasing distance from the source?

(a) Inversely with distance

(b) Inversely with the square of distance

(c) Directly with distance

(d) Directly with the square of distance

17. A weld discontinuity which consists of unmelted joint surfaces at the root, and which
may be caused by poor fit- up, is called:

(a) Hot short cracking

(b) A slag inclusion

(c) Incomplete penetration

(d) Burn through

18. Mottling due to X ray diffraction can be identified by:

(a) Noting a large change between two successive exposures with the test piece
rotated slightly about the beam axis

(b) Noting a slight change between two successive exposures with the test piece
rotated slightly about the beam axis

(c) Noting a characteristic pattern corresponding to the lattice spacing

(d) None of the above

19. Which of the following welding discontinuities would be considered the most serious?

(a) Porosity

(b) Incomplete penetration

(c) Crack

(d) Slag inclusions

20. A depression at the edge of a weld where the base metal has been melted during
welding is called:

(a) Burn through

(b) Undercut

(c) Root concavity

(d) Root convexity

139
 21. Which of the following would not be considered a film artifact?

(a) Sugar

(b) Chemical streaks

(c) PI lines

(d) Pressure marks

22. Gamma ray or high voltage X ray radiography, using film without lead screens, is
likely to result in:

(a) Mottling of the film

(b) Increased geometric unsharpness

(c) No apparent difference, but increased exposure time

(d) No apparent difference, but decreased exposure time

23. Which of the following would be detrimental to radiographic image sharpness?

(a) Small focal spot

(b) Small film focal distance

(c) Small object to film distance

(d) None of the above

24. A change in which the following parameters would require a new X ray exposure
chart?

(a) kV

(b) X ray machine

(c) Test piece thickness

(d) All of the above

25. If the required exposure time for a 1850 GBq (50 curie) Ir-192 source is 4 minutes,
what exposure time would be required for 925 GBq (25 curie) source:

(a) 4 minutes

(b) 8 minutes

(c) 2 minutes

(d) 16 minutes

140
26. A radiograph is made using film X with an exposure of 10 mA-min. Film density
obtained in the area of interest is 1.0. If it is desired to achieve a density of 2.0 in the
area of interest, what exposure is required? (Log relative exposure = 1.1 for a density
of 1.0 and 1.62 for a density of 2.0)

(a) 41.67 mA-min

(b) 10 mA-min

(c) 12.6 mA-min

(d) 33.1 mA-min

27. The least offensive of the following welding discontinuities would probably be:

(a) Incomplete penetration

(b) Lack of fusion

(c) Slag inclusions

(d) Porosity

28. A quantity calculated by the formula, 0.693/(decay constant), is called:

(a) Half value layer

(b) Mass attenuation constant

(c) Half-life

(d) Specific activity

29. The density difference displayed from one area of a film radiograph to another is
called:

(a) Subject contrast

(b) Radiographic contrast

(c) Film contrast

(d) Film latitude

30. The half-life of Co-60 is approximately:

(a) 74 days

(b) 129 days

(c) 5.3 years

(d) 30.1 years

141
 31. Increasing the mA setting on an X ray machine:

(a) Decreases exposure time

(b) Increases exposure time

(c) Increases the short wavelength components of the X ray beam

(d) Decreases the short wavelength components of the X ray beam

32. Which of the following would be considered a film artifact?

(a) Excessive film density

(b) Light leaks

(c) Inadequate penetration

(d) Sugar

33. Which of the following would be detrimental to radiographic image sharpness?

(a) Small focal spot

(b) Large film focal distance

(c) Small object to film distance

(d) None of the above

34. The half-life of Ir-192 is approximately:

(a) 74 days

(b) 129 days

(c) 5.3 years

(d) 30.1 years

35. A dark crescent shaped mark in the centre of a weld bead radiographic image would
probably be:

(a) A film artifact

(b) Porosity

(c) A tungsten inclusion

(d) Root concavity

142
36. A photon-nuclear interaction in which energy is converted into sub-atomic particles is
called:

(a) The photoelectric effect

(b) The Compton effect

(c) Pair production

(d) Bremsstrahlung

37. An interaction in which radiation is produced by the rapid deceleration of an electron

is called:

(a) The photoelectric effect

(b) The Compton effect

(c) Pair production

(d) Bremsstrahlung

38. The gamma factor of Tm-170 is:

(a) 1.37 R·h-1·Ci-1 at one metre

(b) 0.59 R·h-1·Ci-1 at one metre

(c) 0.0062 R·h-1·Ci-1 at one metre

(d) 0.38 R·h-1·Ci-1 at one metre

39. An exposed radiographic film which transmits 1% of the light incident on it has what
density:

(a) 1.0

(b) 2.0

(c) 99.0

(d) 0.5

40. If the radiation intensity is 5 Gy/h (500 R/h) at a distance of 152.4 cm (5 feet) from a
source, what is the intensity at 1524 cm (50 feet)?

(a) 0.5 Gy/h (50 R/h)

(b) 1.0 Gy/h (100 R/h)

(c) 0.1 Gy/h (10 R/h)

(d) 0.05 Gy/h (5 R/h)

143
 41. The average energy of a Cs-137 source is approximately:

(a) 60-80 keV

(b) 660 keV

(c) 400 keV

(d) 1.2 MeV

42. Which of the following is an advantage of X ray over gamma ray sources for
radiography?

(a) Portability

(b) Required maintenance

(c) Variable radiation energy

(d) All of the above

43. The basic purpose of a penetrameter is to:

(a) Indicate quality of the radiographic technique

(b) Indicate the smallest discontinuity which can be shown by the radiographic
technique being used

(c) Serve as a comparison standard for evaluating discontinuity size

(d) All of the above

44. When a casting is being non destructively examined for critical service, and the
possibility of cracks exists, which of the following techniques would be best?

(a) X ray radiography at 200 kV or less

(b) Magnetic Particle or Liquid Penetrant testing

(c) Radiography (X or gamma ray, depending on the thickness)

(d) Radiography and either Magnetic Particle or liquid Penetrant testing

45. Which of the following is an advantage of X ray over gamma ray sources for
radiography?

(a) Safety

(b) Variable radiation intensity

(c) Variable radiation energy

(d) All of the above

144
46. The average energy of a T3-170 source is approximately:

(a) 60-80 keV

(b) 660 keV

(c) 400 keV

(d) 1.2 MeV

47. The gamma factor of Co-60 is:

(a) 1.37 R·h-1·Ci-1 at one metre

(b) 0.59 R·h-1·Ci-1 at one metre

(c) 0.0062 R·h-1·Ci-1 at one metre

(d) 0.38 R·h-1·Ci-1 at one metre

48. The intensifying effect of lead screens is mainly caused by:

(a) X ray generated by the lead screens

(b) Fluorescence of the lead screens

(c) Excited electrons

(d) The Maxwell effect

49. Which of the following expressions correctly determines radiographic density?

(a) Io/It

(b) Log (Io/It)

(c) Log (Io-It)

(d) Io-It

50. The most significant difference in two X ray beams produced at different kV settings
is:

(a) Beam intensity

(b) Exposure

(c) Wavelength distribution

(d) Beam divergence

145
 51. Most significant difference in two X ray beams produced at different mA settings is:

(a) Penetrating power

(b) Wavelength distribution

(c) X ray quality

(d) Beam intensity

52. Which of the following would be considered a film artifact?

(a) Excessive film density

(b) Insufficient film density

(c) Insufficient definition (penetrameter holes)

(d) Static marks

53. Natural discontinuities comparable in size to the penetrameter holes shown on a

radiograph may not be detected because:

(a) Natural discontinuities may contain less dense material than the penetrameter
holes

(b) Natural discontinuities may be thicker than the penetrameter holes

(c) Natural discontinuities do not necessarily have as sharp edges as the

penetrameter holes

(d) All of the above

54. If the radiation intensity is 1 Gy/h (100 R/h) at a distance of 152.4 cm (5 feet) from a
source, what is the intensity at 610 cm (20 feet)?

(a) 0.0625 Gy/h (6.25 R/h)

(b) 0.25 Gy/h (25 R/h)

(c) 16 Gy/h (1600 R/h)

(d) 4 Gy/h (400 R/h)

55. Fluorescent screens are seldom used in industrial radiography because:

(a) Light leaks degrade the film image

(b) Film fogging can result if used in the vicinity of fluorescent lights

(c) Poor definition and screen mottle can result

(d) None of the above

146
56. Calculate geometric unsharpness for the following conditions: Source size = 2 mm × 2
mm; SFD = 700 mm; test piece thickness = 25 mm

(a) 0.6 mm

(b) 0.06 mm

(c) 6,0 mm

(d) 0.15 mm

57. The gamma factor of Ir-192 is:

(a) 1.37 R·h-1·Ci-1 at one metre

(b) 0.59 R·h-1·Ci-1 at one metre

(c) 0.0062 R·h-1·Ci-1 at one metre

(d) 0.38 R·h-1·Ci-1 at one metre

58. A test piece with large differences in thickness would have:

(a) High film contrast

(b) High subject contrast

(c) Low subject contrast

(d) Low film contrast

59. A quantity expressed by the formula, 0.693/(absorption co-efficient) is called:

(a) Half value layer

(b) Mass attenuation constant

(c) Half-life

(d) Specific activity

60. Which of the following techniques would probably reduce the amount of scattered
radiation reaching the film during a radiographic exposure?

(a) Using a finer grained film

(b) Using a filtered X ray beam

(c) Removing lead screens

(d) All of the above

147
 61. A radiographic indication in a weld, characterised by two parallel dark lines in the film
image, would probably be caused by:

(a) Incomplete penetration

(b) Lack of fusion

(c) Slag inclusions

(d) Tungsten inclusions

62. To produce the sharpest image, which of the following should be true?

(a) The radiographic source should be small

(b) The radiographic source should be as close as possible to the test piece

(c) The planes of the test piece and the film should be at oblique angles to each
other

(d) All of the above

63. ‘Undercut’ or ‘burned out’ edges of the test piece film image are caused by:

(a) Geometric unsharpness

(b) Scattered radiation

(c) Inadequate source to film distance

(d) Old film

64. Which of the following is an advantage of gamma ray over X ray sources for
radiography?

(a) Portability

(b) No external power supply needed

(c) Ruggedness

(d) All of the above

65. The intensifying effects of fluorescent screens are caused by:

(a) Electron emission

(b) Light emission

(c) Secondary X rays

(d) All of the above

148
66. If the required X ray exposure time for a 225 kV, 5 mA exposure is 3 minutes,
approximately what exposure time would be required at 10 mA?

(a) 1/2 minute

(b) 1 minute

(c) 1.5 minutes

(d) 3 minutes

67. The half-life of Cs-137 is approximately:

(a) 74 days

(b) 129 days

(c) 5.3 years

(d) 30.1 years

68. Unacceptable radiographic film quality would be indicated by:

(a) Artifacts of known origin in the film's area of interest

(b) Use of a smaller penetrameter than required

(c) H & D density less than 2.0

(d) All of the above

69. Which of the following welding discontinuities would be most difficult to image
radiographically:

(a) Porosity

(b) Lack of side wall fusion

(c) Undercut

(d) Slag inclusions

70. The most important factor in limiting radiation exposure is:

(a) Time

(b) Distance

(c) Shielding

(d) All of the above

149
 71. The threshold energy below which pair production cannot occur is approximately:

(a) 100 keV

(b) 1 MeV

(c) 10 MeV

(d) 20 MeV

72. A photon-electron interaction in which a photon gives up all its energy to an electron
is called:

(a) The photoelectric effect

(b) The Compton effect

(c) Pair production

(d) Bremsstrahlung

73. An acceptable quality radiograph should include:

(a) Proper identification

(b) Correct penetrameter and visible holes

(c) Location markers

(d) All of the above

74. For gamma ray sources, radiographic intensity is proportional to source activity in
gigabecquerels or curies for:

(a) All sources

(b) Large sources

(c) Small sources

(d) None of the above

75. Poor contact between lead screens and film is likely to cause:

(a) An indistinct or ‘fuzzy’ image

(b) A mottled appearance on the film

(c) ‘Undercut’ of the test piece image

(d) Increased geometric unsharpness

150
76. Which of the following conditions might cause mottling of a radiographic film?

(a) Test piece with thickness equal to an integral multiple of the primary beam
wavelength

(b) Back scatter from aged fluorescent screens

(c) Test piece with thickness of the same order of magnitude as the grain size

(d) Test piece with thickness equal to an integral multiple of the average grain size

77. A photon-electron interaction in which a photon gives up a portion of its energy to an

electron is called:

(a) The photoelectric effect

(b) The Compton effect

(c) Pair production

(d) Bremsstrahlung

78. If the radiation intensity is 5.9 Gy/h (590 R/h) at a distance of 30.5 cm (1 foot) from a
source, how far is it to the point where the radiation intensity is 0.02 Gy/h (2 R/h)?

(a) 518 cm (17 feet)

(b) 16551 cm (543 feet)

(c) 8291 cm (272 feet)

(d) 17983 cm (590 feet)

79. It is important to initiate the welding arc within the weld groove because:

(a) Starting a weld bead outside the groove may overheat the base metal

(b) Too rapid heating and cooling of the base metal can cause hard spots which are
potential failure initiation sites

(c) Starting a weld bead outside the groove results in excessively wide welds

(d) None of the above

80. If the radiation intensity is 5 Gy/h (500 R/h) at a distance of 152.4 cm (5 feet) from a
source, how far is it to the point where the radiation intensity is 0.05 Gy/h (5 R/h)?

(a) 1676.4 cm (55 feet)

(b) 1981 cm (65 feet)

(c) 1524 cm (50 feet)

(d) 762 cm (25 feet)

151
 81. Which of the following techniques would probably reduce the amount of scattered
radiation reaching the film during a radiographic exposure?

(a) Using a finer grained film

(b) Masking the test piece

(c) Removing lead screens

(d) All of the above

82. The lights in a high intensity viewer are typically:

(a) Fluorescent

(b) Normal incandescent bulbs

(c) Photoflood bulbs

(d) Mercury vapour lamps

83. The gamma factor of Cs-137 is:

(a) 1.37 R·h-1·Ci-1 at one metre

(b) 0.59 R·h-1·Ci-1 at one metre

(c) 0.0062 R·h-1·Ci-1 at one metre

(d) 0.38 R·h-1·Ci-1 at one metre

84. If the required X ray exposure time for a 150 kV, 5 mA exposure is 2 minutes,
approximately what exposure time would be required at 10 mA?

(a) 1/2 minute

(b) 1 minute

(c) 2 minutes

(d) 4 minutes

85. A thin, jagged, dark line inside the weld image on a radiographic film is probably:

(a) Incomplete penetration

(b) Lack of fusion

(c) Burn through

(d) A crack

152
 86. A straight, dark line in the centre of a weld bead image on film would be suspected of
being:

(a) Lack of fusion

(b) A crack

(c) Incomplete penetration

(d) Root concavity

87. ‘Undercut’ or ‘burned out’ edges of the test piece in film image can usually be reduced
by:

(a) Increasing source to film distance

(b) Decreasing the thickness of the lead screens

(c) Placing a thin sheet of lead behind the cassette

(d) Masking the test piece

88. Which of the following would be detrimental to radiographic image sharpness?

(a) Small focal spot

(b) Large film focal distance

(c) Large object to film distance

(d) None of the above

3.2.2 Radiographic Testing Level 2 (RT-2) Specific Examination

1. Contrast and definition are the two major factors that determine the _____________ of
the radiograph:

(a) Density

(b) Sensitivity

(c) Graininess

(d) Intensity

2. Scatter radiation:

(a) Is not controllable

(b) Is controllable to some extent, but cannot be completely eliminated

(c) Can be eliminated completely by changing the kV

(d) Can be eliminated completely by using lead intensifying screens

153
 3. Which of the following factors will affect the definition of the radiographic image?

(a) Intensity of radiation

(b) Film density

(c) Tube current

(d) Focal spot size

4. Slow films:

(a) Give better definition than fast films

(b) Are faster than fast films

(c) Require shorter exposure times than fast films

(d) Usually have less contrast than fast films

5. Contrast is defined as the comparison between _______________ on different areas of

the radiograph:

(a) Density

(b) Sensitivity

(c) Sharpness

(d) Latitude

6. Definition is defined as the measure of the _______________ of the outline of the

image in the radiograph.

(a) Density

(b) Sensitivity

(c) Sharpness

(d) Latitude

7. As radiation (X ray or gamma ray) energy is lowered:

(a) Radiation of longer wavelength and better penetration is produced

(b) Radiation of shorter wavelength and better penetration is produced

(c) Radiation of shorter wavelength and less penetration is produced

(d) Radiation longer wavelength and less penetration is produced

154
8. Dark crescent-shaped indications on a radiographic film are most likely caused by:

(a) Crimping film after exposure

(b) Crimping film before exposure

(c) Sudden extreme temperature change while processing

(d) Warm or exhausted fixer

9. Lead screen are primarily used to:

(a) Improve the quality of the radiography by increasing the effect of scatter
radiation

(b) Intensify the primary beam

(c) Decrease film graininess

(d) Reduce density of film

10. Static marks are most often caused by:

(a) Film bent when inserted in a cassette or holder

(b) Foreign material or dirt imbedded in screens

(c) Scratches on lead foil screens

(d) Improper film handling techniques

11. When radiographic energy is decreased:

(a) The subject contrast decreases

(b) The film contrast decreases

(c) The subject contrast increases

(d) The film contrast decreases

12. The major cause for poor definition is:

(a) A source-to-film distance which is too long

(b) Screens which are too thin

(c) Film graininess

(d) Too small a source size

155
 13. In order to increase latitude so that thick and thin portions may be radiographed at
reasonable viewing densities simultaneously:

(a) Fluorescent screen should be employed

(b) Led screens should be at least 5 mm thick

(c) The cassette may be loaded with two separate films of different speeds

(d) Radiograph the object at low energy

14. A dark circle type indication appearing on a radiograph that is the result of the failure
of a core support to completely melt is called:

(a) A hot tear

(b) A gas hole

(c) An unfused chaplet

(d) A spongy shrink

15. Dark rounded indications with rather smooth edges appear on the radiograph of
casting made in sand mould. These indications would be interpreted as:

(a) Slag inclusions

(b) Misrun

(c) Shrinkage

(d) Gas holes

16. A dark, sharply defined, straight line in the centre of the weld, and running parallel
with the length of the weld should be interpreted as:

(a) Porosity

(b) Incomplete penetration

(c) A slag inclusion

(d) Lack of fusion

17. A dark, jagged, linear indication appears on a radiograph of a casting. The area is a
transition area between a thick and a thin section. This indication should be interpreted
as:
(a) A hot tear
(b) A gas hole
(c) An unfused chaplet
(d) A spongy shrink

156
18. In a radiograph of a weld there is an indication appearing at the end of the weldbead. It
appears as a dark rounded indication with fine small tails coming from around the
rounded indication giving it some what of a star-shaped appearance. This would
probably be:

(a) A crater crack

(b) A slag inclusion

(c) Root concavity

(d) A star crack

19. The density of the radiograph through the weld area is 3.2 while the density in the
base metal is 2.9. This would probably indicate:

(a) Too high a kV was used

(b) Too low a kV was used

(c) There is excessive weld reinforcement

(d) Weld underfill

20. When radiographing a part which contains a crack, it will appear on the radiograph as:

(a) A dark continuous line

(b) A light, irregular line

(c) Either a dark or light line

(d) A dark linear indication which could be continuous or intermittent

21. If it were necessary to radiograph 18 cm (7 in.) thick steel product, which of the
following gamma ray sources would most be used?

(a) Cs–137

(b) Tm–170

(c) Ir–192

(d) Co–60

22. Almost all gamma radiography is performed with:

(a) Tm-170

(b) Natural isotopes

(c) Radium

(d) Ir-192 or Co-60

157
 23. The half value layer of lead for Co-60 is approximately 13 mm (0.5 in). If the
radiation level on the source side of a 38 mm (1.5 in) lead plate is 0.64 Gy/h (64 R/h):,
the radiation level on the opposite side is:

(a) 0.08 Gy/h (8 R/h).

(b) 0.213 Gy/h (21.33 R/h).

(c) 0.107 Gy/h (10.67 R/h).

(d) 0.32 Gy/h (32 R/h).

24. The degree of concentration of the radioactive material in gamma ray sources is
referred to as the:

(a) Atomic weight of the source

(b) Half-life of the source

(c) Quality of the source

(d) Specific activity of the source

25. If 37 GBq (1 Ci), of Ir-92 produces dose rate of 0.59 Gy/h (59000 mR/h) at 30.5 cm
(1 foot), how much dose in Gy/h (R/h) will 370 GBq (10 Ci) produce at the same
distance?

(a) 0.59 Gy/h (59000 R/h)

(b) 0.0059 Gy/h (590 R/h)

(c) 5.9 Gy/h (590,000 R/h)

(d) 0.00059 Gy/h (59 R/h)

26. Co-59 becomes Co-60 when it is placed in a nuclear reactor where it captures:
(a) A proton
(b) Contamination
(c) Neutron
(d) An electron
27. Approximately how long would it take for a 370 GBq (10 Ci) Co-60 source to decay
to 92.5 GBq (2.5 Ci)?
(a) 5.3 days
(b) 5.3 years
(c) 10.6 days
(d) 10.6 years

158
28. An NDT technician is using a 740 GBq (20 Ci) source of Ir-192, he is standing at a
distance of 305 cm (10 feet). What dose rate will he receive? (Show your working)

29. In the above question, at what distance from the source the technician be to receive 20
mSv/h (2R/h)?

30. The dose rate for a technician standing 610 cm (20 ft), from a 1295 GBq (35 Ci) Ir-
192 source is 5.16 mSv (516.25 mR/h). If he continues standing at his location, how
much lead shielding will be required to reduce the dose rate to 0.02 mSv (2mR/h)?

31. The specific activity of radioactive isotope is expressed in:

(a) MeV (million electron-volts)

(b) Ci/g (Curies per gram) or Becquerel per kg

(c) R/h (Roentgens per hour or gray per hour

(d) Counts per minute

32. The general method of producing X rays involves the sudden deceleration of high
velocity electrons in a solid body called a:

(a) Focus cup

(b) Filament

(c) Target

(d) Cathode

33. The velocity of electrons striking the target in an X ray tube is a function of:

(a) The atomic number of the cathode material

(b) The atomic number of the filament material

(c) The voltage applied

(d) The current flow in the tube

34. The primary form of energy conversion when an X ray tube is energized results in the
production of:

(a) Primary X rays

(b) Secondary X ray

(c) Short wavelength X ray

(d) Heat

159
 35. The radiation from 37 GBq (1 Ci) of Co-60 (0.145 Gy or 14.5R at 30.5 cm or 1 foot)
is attenuated in air to approximately 5mR/h at a distance of approximately:

(a) 914.5 cm (30 feet)

(b) 1524 cm (50 feet)

(c) 3048 cm (100 feet)

(d) 6096 cm (200 feet)

36. The standard dose rate of a radioactive isotope is expressed in:

(a) Roentgens per hour per curie at any standardised distance not exceeding 75
feet

(b) Roentgens per hour per curie per foot

(c) Roentgens per hour at a distance of one foot

(d) Curies per hour

(e) Distance required to 2 mR/h

37. Tick the items that are characteristic of X or gamma radiation:

is a particle has mass

ionizes matter travels at the speed of light

harmful to humans has high frequency

38. Tick the items that are characteristic of X or gamma radiation:

is electromagnetic penetrates matter

has odour is visible

causes fluorescence is non-destructive to

in some materials humans

39. At 61 cm (two feet) from a radiation source, radiation intensity is 3 Gy/h (300 R/h).
What is the Intensity at 244 cm (8 feet) from the source?
(a) 0.12 Gy/h (12 R/h)
(b) 1.2 Gy/h (120 R/h)
(c) 0.1875 Gy/h (18.75 R/h)
(d) 0.28 Gy/h (28 R/h)

160
40. Define the following by selecting appropriate numbers from the second column:

curie 1. Million electron volts

roentgen 2. Unit of absorbed dose of radiation

Half value layer 3. Geometric unsharpness

kVp 4. Milliampere × minute

MeV 5. Time required for a radioactive isotope to

lose half of its original activity

Ug 6. Rate of disintegration of a radioactive

isotope

rad 7. Curie per gram

mA-min 8. Kilovolt peak

Half-life 9. Thickness of material which reduces the

radiation to half of its original intensity

definition 10. Degree of image sharpness

41. Number these radiographic film processing steps in their correct sequence:

Stop Bath Fixing

Wetting Agent Washing

Developing Drying

42. Source to film distance for first exposure is 91.5 cm (36 inches) and is changed to 122
cm (48 inches) for the second exposure. Time #1 was 900 mA-sec. How many mA-
min will the second exposure require?

Answer: ___________________________________________________________

161
 43. A good Cobalt-60 shot is made on a 7.6 cm (3 inches) steel casting using an exposure
time of 10 minutes and a source-to-film distance of 91.5 (36 inches). If it is necessary
to change the source-to-film distance to 61 cm (24 inches), what exposure time would
produce a similar radiograph if all other conditions remain the same?

(a) 1.6 minutes

(b) 4.4 minutes

(c) 6.4 minutes

(d) 8.8 minutes

44. A radiographic exposure with 3700 GBq (100 Ci) source of Ir-192 using source to
film distance of 60 cm results in a radiation intensity of 0.12 Gy/h (11.8 R/h) and a
radiographic density of 2.5. The intensity of radiation needed to obtain the same
density when the source to film distance is changed to120 cm is:

(a) 0.472 Gy/h (47.2 R/h)

(b) 0.118 Gy/h (11.8 R/h)

(c) 0.029 Gy/h (2.9 R/h)

(d) 0.236 Gy/h (23.6 R/h)

45. A 7.6 cm (3 inches) thick test specimen is radiographed with a source having size of
1.3 cm (1/2 inch), the film is placed in contact with the test specimen. The source to
film distance is 40.6 cm (16 inches).The geometric unsharpness obtained is:

(a) 0.1 cm

(b) 0.3 cm

(c) 0.5 cm

(d) 1.0 cm

46. Radiographic equivalence factors for Inconel and 304 stainless steel are 1.4 and 1.0
respectively. What is the approximate equivalent thickness of Inconel requiring the
same exposure as 1.27 cm (½ inch) thickness of 304 stainless steel?

(a) 1.27 cm (0.50 inches)

(b) 1.78 cm (0.70 inches)

(c) 0.9 cm (0.36 inches)

(d) 3.55 cm (1.40 inches)

162
47. The approximate radiographic equivalence factors for steel and copper at 220 kV are
1.0 and 1.4 respectively. If it is desirable to radiograph a 1.27 cm (0.5 inch) piece of
copper, what thickness of steel would require about the same exposure characteristics?

(a) 1.78 cm (0.7 inches)

(b) 0.9 cm (0.35 inches)

(c) 3.55 cm (1.4 inches)

(d) 2.54 cm (1.0 inch)

48. If an exposure time of 60 seconds and source to film distance of 365.7 m (1200 feet) is
necessary for a particular exposure, what exposure time would be needed for an
equivalent exposure if the source- to-film distance is changed to 457.2 m (1500 feet)?

(a) 75 seconds

(b) 94 seconds

(c) 48 seconds

(d) 38 seconds

49. The technique requires 2500 mA-sec exposure. How long would the exposure time be
in minutes using:

(a) 5 mA Answer: _______________________________

(b) 10 mA Answer: _______________________________

50. Using a 250, kV 10 mA X ray unit, the technique chart indicates an exposure time of
1200 mA-sec. Using maximum mA, how many minutes should be used?

Answer: ___________________________________________________________

51. Source to film distance for first exposure is 91.5 cm (36 inches) and is changed to 60.1
cm (24 inches) for the second exposure. Time #1 was 900 mA-sec. How many
minutes will the second exposure require at the same mA?

Answer: ___________________________________________________________

52. Subject contrast and film contrast are the two factors that comprise radiographic:

(a) Definition

(b) Distortion

(c) Contrast

(d) Graininess

163
 53. Scatter ___________________ radiographic contrast.

(a) Reduces

(b) Increases

(c) Does not affect

54. ‘Film contrast’ is the inherent ability of a film to show ___________________ for a
given change in film exposure.

(a) No appreciable change in density

(b) Graininess

(c) A difference in density

(d) No graininess

55. The range of the specimen thickness that can be adequately recorded on a radiograph
is known as the ___________________ of the radiograph.

(a) Sensitivity

(b) Latitude

(c) Accuracy

(d) Intensity

56. Source-to-object distance, object-to-film distance, and source size are the three factors
that control the ___________________ of the radiograph.

(a) Density

(b) Exposure

(c) Film size

(d) Unsharpness

57. The ‘multi-film’ technique may be used when one radiograph film does not have
enough ___________________ to produce a satisfactory radiograph of a specimen.

(a) Latitude

(b) Definition

(c) Graininess

(d) Activity

164
58. When a fast film and a slow one are loaded in the same cassette (multi-film
technique), the slow film can be expected to record adequately the
___________________ (thinner) or (thicker) sections of a specimen.

59. What governs the penetrating power of an X ray beam?

(a) Kilovoltage

(b) Time

(c) Activity

(d) Milliamperage

60. The shorter the wavelength of X or gamma rays:

(a) The higher their energy

(b) The faster they travel

(c) The smaller their penetrating power

(d) The closer they are to becoming radio waves

61. A large source size can be compensated for by:

(a) Increasing source-to-specimen distance

(b) Addition of lead screens

(c) Increasing specimen-to-film distance

(d) Increasing penumbra

62. The maximum film density to which the radiograph should be exposed is dependent
upon:

(a) The quality of the film viewer

(b) The variation in thickness of the specimen

(c) The speed of the film

(d) The graininess of the film

63. The selection of the proper source-to-film distance is a primary factor in controlling:

(a) Contrast

(b) Unsharpness

(c) Graininess

(d) Scatter

165
 64. When the penumbra on a radiograph measures less than 0.5 mm (0.020 inches), the
image will appear to unaided eye of the film interpreter as:

(a) Fuzzy

(b) Sharp

(c) Distorted

(d) Dark

65. Two X ray machines operating at same nominal kilovoltage and milliamperage
settings:

(a) Will produce the same intensities and energies of radiation

(b) Will produce the same intensities but produce different energies of radiation

(c) Will produce the same energies but may produce different intensities of
radiation

(d) May give not only different intensities, but also different energies of radiation

66. The fact that gases, when bombarded by radiation, ionise and become electrical
conductors make them useful in:

(a) X ray transformers

(b) X ray tubes

(c) Masks

(d) Radiation detection equipment

67. An acceptable quality radiograph should include:

(a) Proper identification

(b) Correct penetrameter and visible holes

(c) Location markers

(d) All of the above

68. A weld discontinuity which consists of unmelted joint surfaces at the root, and which
may be caused by poor fit-up, is called:

(a) Hot short cracking

(b) A slag inclusion

(c) Incomplete penetration

(d) Burn through

166
69. Which of the following welding discontinuities would be most difficult to image
radiographically:
(a) Planar lack of fusion
(b) Incomplete penetration
(c) Undercut
(d) Slag inclusions

70. The average energy of a Ir-192 source is approximately:

(a) 60-80 keV
(b) 660 keV
(c) 400 keV
(d) 1.2 MeV

72. The half-life of Th-170 is approximately:

(a) 74 days
(b) 129 days
(c) 5.3 years
(d) 30.1 years

73. If the required exposure time for a 50 Curie Ir-192 source is 4 minutes, what exposure
time would be required at 25 Curie source:
(a) 4 minutes
(b) 8 minutes
(c) 2 minutes
(d) 16 minutes

74. Which of the following is not a function of the lead screen placed around radiographic
film?
(a) Increase the photographic action on the film
(b) Selectively absorbs scattered radiation
(c) Intensifies effects of the primary radiation beam
(d) To mask the test piece

75. Which of the following is a function of the lead screen placed around radiographic film?
(a) Masks the test piece
(b) Improves geometric unsharpness
(c) Intensifies effects of the primary radiation beam
(d) None of the above

167
76. What is the best advantage achieved in exposure time, using front and back lead
screens, as compared to exposure time without screens?

(a) About the same, but less scatter

(b) About twice as great, but less scatter

(c) 1/2 to 1/3

(d) Not related

77. Gamma ray or high voltage X ray radiography, using film without lead screens, is likely
to result in:

(a) Mottling of the film

(b) Increased geometric unsharpness

(c) No apparent difference, but increased exposure time

(d) No apparent difference, but decreased exposure time

78. Fluorescent screens are seldom used in industrial radiography because:

(a) Light leaks degrade the film image

(b) Film fogging can result if used in the vicinity of fluorescent lights

(c) Poor definition and screen mottle can result

(d) None of the above

79. An advantage of a double versus a single emulsion film is:

(a) It is higher speed

(b) It is finer grained

(c) It is lower speed

(d) None of the above

80. A radiograph is made using film X with an exposure of 10 mA-min. Film density in the
area of interest is 1.0. If it is desired to achieve a density of 2.0 in the area of interest,
what exposure is required? (Log relative exposure = 1.1 for a density of 1.0 and 1.62 for
a density of 2.0)

(a) 41.67 mA-min

(b) 10 mA-min

(c) 12.6 mA-min

(d) 33.1 mA-min

168
3.2.3 Radiographic Testing Level 2 (RT-2) Answers to questions

Radiographic Testing Level 2 Answers to Questions

General Examination Specific Examination
1 a 35 a 69 b 1 b 35 b 69 a
2 b 36 c 70 d 2 b 36 c 70 d
3 b 37 d 71 b 3 d 37 * 71 b
4 d 38 c 72 a 4 a 38 * 72 b
5 b 39 c 73 d 5 a 39 c 73 b
6 c 40 d 74 a 6 c 40 * 74 b
7 a 41 b 75 a 7 d 41 * 75 c
8 b 42 c 76 b 8 a 42 * 76 c
9 d 43 a 77 b 9 b 43 b 77 a
10 d 44 b 78 a 10 d 44 c 78 c
11 a 45 d 79 d 11 c 45 b 79 a
12 b 46 a 80 c 12 c 46 c 80 d
13 d 47 a 81 b 13 c 47 a
14 d 48 c 82 c 14 c 48 b
15 a 49 b 83 d 15 d 49 *
16 b 50 c 84 b 16 b 50 *
17 c 51 d 85 d 17 a 51 *
18 b 52 d 86 c 18 d 52 c
19 c 53 c 87 d 19 d 53 a
20 b 54 a 88 c 20 d 54 c
21 a 55 c 21 d 55 b
22 a 56 d 22 d 56 d
23 b 57 b 23 d 57 a
24 b 58 b 24 a 58 *
25 b 59 a 25 c 59 a
26 a 60 b 26 c 60 a
27 d 61 b 27 d 61 a
28 c 62 a 28 * 62 a
29 b 63 b 29 * 63 b
30 c 64 d 30 * 64 b
31 a 65 b 31 b 65 d
32 b 66 c 32 c 66 d
33 b 67 d 33 c 67 d
34 a 68 d 34 c 68 c

169